Electronic pens can be used for various purposes, for instance scanning, position detection, etc. Examples of the mechanics and structures of such electronic pens are disclosed for instance in applicant's WO 03/001358, WO 02/093467 and WO 02/103623. Further examples of the mechanics, optical systems and software of such electronic pens are disclosed for instance in applicant's WO 06/006925, WO 06/004506, WO 05/057471, WO 03/069547, WO 03/046708 and WO 03/001440, and references therein.
Recently, a special type of such electronic pens with audio feedback capability has gained success on the market. In particular, these audio-enabled pens are designed for the toy and learning market. Such pens are marketed under the product name “FLY™ Pentop Computer” by Leapfrog Enterprises, Inc. A pen of this structure has a casing and a tip projecting from the same. An optical scanner is arranged in the casing to capture images of the surface on which the pen is operated. The surface may be a so-called dot-matrix paper comprising a position-coding pattern. When a user moves the tip on this surface, processing circuitry in the pen processes the images to electronically determine the position and movement of the pen on the surface. The pen has an audio function which means that it outputs audio signals in response to certain “hits” or movements of the tip on the dot-matrix paper. For instance, if the tip is put on a map of the United States, a voice of the audio system may, via a speaker, tell you which state the tip is put on.
However, existing electronic pens of this kind have certain drawbacks which will be discussed in the following.
The pens are rather large sized, which makes them cumbersome and sometimes hard to handle. There is a demand for a small-size pen of compact structure.
Furthermore, certain parts contained in the known pens are fastened to the inside of the casing which may constitute weak attachment points. It may also happen that electric wires and contacts between the components loosen when the pen is dropped or thrown against something. For example, sensitive components can be destroyed if an impact on the tip is transferred into the interior of the pen.
As to the audio system, the speaker is often simply mounted on the inside of the pen casing, which means that it is exposed to the entire inner volume of the large-size pen. This may result in poor sound quality, and it may also happen that the speaker comes loose from its attachment.
The manufacturing process of these pens is complicated since a plurality of parts and components are involved, some of which have to be connected by several electric wires which may come loose, as discussed above. A more effective and secure manufacturing process is desirable. Finally, the tamper proof function of these known pens is not sufficient since it is easy to dismantle the pen and manipulate the sensitive components.